The present invention relates to a new sanitary system, especially a system or aggregate for delivery of hot and cold water to a plurality of outlet locations. The invention relates further to a thermostatically controlled mixing valve unit, and a piping structure, particularly useful in the system.
Conventional sanitary systems for delivery of hot and cold water to a plurality of outlet locations, for instance in a private house, comprises a source for cold water, a hot water storage heater with a cold water supply, a piping system to the outlet locations consisting of a cold water pipe and a hot water pipe, and a mixer valve at the tapping position. The piping in the system consists frequently of a set of main pipes, and paired branch pipes to the separate tapping locations. The tapping valves or mixing valves may be of the two-handle type or the one-handle type such that the user by means of two manual movements adjusts the water temperature and the water quantity, respectively.
In recent years it has been quite usual to use so called thermostatic mixing faucets, particularly in bathrooms such that one may pre-adjust the water temperature on a scale displaying the water temperature, and such that one may with one single handle adjust the water quantity.
Conventional sanitary systems for delivery of hot and cold water have reached a high quality, but known systems are still hampered with some inherent drawbacks which have proved difficult to overcome. Firstly, such sanitary systems are rather expensive both to purchase and install, and they require further substantial maintenance, such as replacement of valve packings, etc.
In practical use the drawback frequently occurs that when tapping hot water one must readjust the water temperature several times during the tapping operation, among other reasons because of heating up of the piping system. A further drawback is the creation of pressure drops, sometimes also with abrupt temperature variations, if hot water is being discharged at two or several outlets simultaneously. A further drawback is that delivery of water with high temperature to the various outlets causes large wear on the valves and the packings.
A more serious drawback with known systems is, however, the large heat loss which takes place due to the heating of the pipe system and the fact that by each tapping a relatively large column of hot water will remain standing unused in the piping system.
A further substantial drawback with conventional sanitary systems of this kind is that they cause the creation of substantial piping noise and so called "water shocks". Piping noise is created in the piping as such, particularly in connection with transitions and fittings, as well as in the mixing valves due to the inherent turbulence therein. Such piping noise has proved to be very difficult to diminish, and frequently causes irritation.
By utilization of thermostatically controlled mixing valves it is simpler to tap tempered water with a suitable temperature, but such arrangements are rather expensive and require substantial maintenance if the adjusting ability is to be maintained over a long period of time.